Customers can donate 'store cupboard items' through the Sainsbury's and FareShare food poverty scheme for the Guardian. Photograph: Martin Godwin

A supermarket initiative is set to generate more than 500 tonnes of food donations – the equivalent of 1m meals – which will be distributed to regional charities to help feed disadvantaged and homeless people over Christmas.

The One Million Meal Appeal, which will be launched on 26 November, gives customers the opportunity to add an extra store cupboard item such as tins, dried pasta and rice to their shopping basket or trolley, which will then be delivered to local community projects by food poverty charity FareShare.

The appeal is being rolled out at all Sainsbury's supermarkets, as well as a number of convenience stores, following a successful trial in July when customers donated 25 tonnes of food in three days. For every meal generated by its customers Sainsbury's will donate 25p.

Sainsbury's retail and logistics director Roger Burnley said: "When we ran the trial of this scheme we were overwhelmed by the generosity of customers. It seems that even though household budgets are under pressure, people are still keen to help those less fortunate."

FareShare redistributes quality surplus food from the food industry to people in need. Sainsbury's has been working with it since 1994, but this is the first time customers across the UK have been asked to actively take part.

The initiative was welcomed by minister for civil society, Nick Hurd, who said: "Sainsbury's progressive initiative with FareShare will encourage consumers up and down the country to get involved in their local community and support the vulnerable and needy – it is a great example of the principles of Every Business Commits, this coalition government's strong belief that every business can play a positive role in society."

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